Attachment means for pocket or buttonhole slitter



April 29, 1969 E. SEAMAN 3,440,982

7 ATTACHMENT MEANS FOR POCKET OR BUTTONHOLE SLITTER Filed Nov. 7, 1967Sheet INVENTOR. EDWARD 554m BI Z,

April 29, 1969 E. SEAMAN 3,440,982

ATTACHMENT MEANS FOR POCKET OR BUTTONI-IOLE SLITTER med Nov. 7. 1967Sheet 3 of 4 INVENTOR. fDH/Akfl 554m April 29, 1969 E, E M N 3,440,982

ATTACHMENT MEANS FOR POCKET OR BUTTONHOLE SLITTER Filed Nov. 7, 1967Sheet of 4 F i E INVENTOR.

L DW/MD- SEA/ 44M Arron/ r April 29, 1969 E. SEAMAN 3,440,982

ATTACHMENT MEANS FOR POCKET OR BUTTONHOLE SLITTER Filed Nov. 7, 1967Sheet 4 or 4 INVENTOR. fDW/IRD; SEAMAN United States Patent 3,440,982ATTACHMENT MEANS FOR POCKET 0R BUTTONHOLE SLITTER Edward Seaman, 65Harvard St., Garden City, N.Y. 11530 Filed Nov. 7, 1967, Ser. No.681,266 Int. Cl. Db 3/00, 37/00 U.S. Cl. 112-68 12 Claims ABSTRACT OFTHE DISCLOSURE In the formation of pockets, buttonholes and the like inthe mass production of garments, it is conventional to use a Z-needlesewing machine such as a Singer or Union Special designed tosimultaneously slit and sew a plurality of overlying fabrics fed to themachine, the slit being of lesser length than and in inwardly spacedrelation to the ends of the rows of stitching to permit the folding backand finishing of the pocket or buttonhole. Although special sewingmachines have been designed to accomplish such sewing and slittingoperations, the mechanism built into such machines is usuallycomplicated, hence the machines are costly. Moreover, so far as I amaware none of such machines is capable of automatically varying thelengths of the slits in relation to the rows of stitching withoutmodifying the machine nor are such machines capable of automaticallystopping the slitting and sewing operations at will.

Accordingly, among the objects of the present invention are (a) toprovide attachment means to a commercial sewing machine, said meanscomprising a slit cutter adapted for attachment to the needle 'bar ofsuch sewing machine to form in the work pieces a slit progressively withthe sewing operation, and to vary the length of the slit in relation tothe length of the stitchingj (b) to automatically withdraw the slitcutter from its slitting position independently of the sewing operation;and (c) to automatically stop the sewing operation at a predeterminedrelation to that whereat the slit cutter is withdrawn.

The foregoing and other objects of the invention, not specificallyenumerated, I accomplish with the attachment means of the presentinvention, the construction and operation of which will be understoodfrom the detailed description which follows when considered inconnection with the accompanying drawings wherein:

FIG. 1 is a front elevational view of a conventional double-needlesewing machine, with parts broken away, to which the attachment means ofmy invention is applied.

FIG. 2 is a top plan view taken along the line 22 of FIG. 1 with theleft-end portion thereof broken away to better illustrate the invention.

FIG. 3 is an end elevational view of portions of the attachment meansshown in FIG. 2 as viewed from the right-hand end thereof.

FIG. 4 is a cross-sectional view taken along the line 44 of FIG. 3.

FIG. 5 is a sectional view taken along the line 5-5 of FIG. 4.

. 2 3,440,982 Patented Apr. 29, 1969 ice FIG. 6 is a perspective view ofportions of the operational means for withdrawing the slit cutter fromcutting position and for stopping the sewing operation, as viewed in thedirection of the arrows on the line 6-6 of FIG. 1.

FIGS. 7 to 9 are elevational views of the slit cutter and the means foroperating the same in operative and inoperative positions.

FIG. 10 is a top plan view of the relationship of the work pieces in apreliminary stage of forming a pocket in a garment.

FIG. 11 shows the wiring diagram of the electrical means employed in theoperation of the attachment means.

Referring to the drawings in the several figures of which correspondingparts are designated by the same reference characters, the attachmentsof the present invention are intended for application to a conventionalsewing machine, such as a Singer or a Union Special for forming pipedpockets or buttonholes of any desired length by simultaneously slittingand sewing garment fabrics in which such pockets or buttonholes are tobe formed. Such sewing machines usually comprise a head 12, a needle bar14 reciprocable in a well-known manner by a rotatable shaft .16 drivenby the power source for the sewing machine.

Attached to and reciprocable with the needle bar is a needle clamp 18 inwhich may be secured a pair of laterally-spaced needles 20. Fixedlycarried by a holder 22 which is pivotally mounted at 24 to the needleclamp is a cutter blade 26 movable between and with the needles from anormal non-cutting position as shown in FIGS. 8 and 9 to a cuttingposition as shown in FIG. 7. Normally, the holder 22 is biased by a leafspring 72 affixed to the needle clamp to urge and maintain the holder 22and with it the blade, upwardly into noncutting position until physically moved downwardly against the force of the spring. For moving thecutter blade into cutting position is an angular lever 28, one arm 28aof which is pivoted at 30 to the needle clamp 18 and said arm is formedwith a cam surface 32 adapted to engage and hold the holder 22downwardly when the other arm 28b is moved upwardly. As shown in FIGS. 7and 8 the cutting edge 26a of the blade 26 is offset and is disposedrearwardly in relation to the needles 20 in the direction of the sewingand slitting operation, so that when beginning the sewing operation, theslitting of the fabrics rearwardly of the sewing will simultaneouslytake place to provide for the finishing operation of the pocket in aconventional manner.

Referring now to FIGS. 1 to 5 of the drawings the attachment means ofthe invention requires the removal from the drive shaft 16 of theconventional pulley usually mounted on said shaft and driven from thepower source of the machine and in lieu of such pulley there is fixedlymounted on said shaft a twin driving pulley 34, 34a. The pulley 34 isadapted to be driven by a belt 36 trained over a hub 38 extending from apulley 40 mounted loosely on a stub shaft 42 mounted in an arm 44a of abracket 44 mounted on the table 46 of the sewing machine. Also mountedloosely on the shaft 42 is a pulley 48 over which is trained a belt 50driven by the power source (not shown) of the machine. Also mountedloosely on the shaft 42 but physically connected to the hub 38 is arotatable clutch element 52, see FIG. 5, having a recess 54 adapted toreceive a detent 56 to normally prevent rotation of the clutch elementand with it the hub 38 and pulley 40.

Mounted on the arm 44!; of the bracket 44 is a bifurcated bracket orclevis 58 in which is pivotally mounted on a pin 59, a lever 60, theupper end of which has a lateral extension which constitutes the detent56 which also extends through and is slidable in a slot 62 formed in theupper end of the bracket arm 44a. The lever 60 is biased by a leafspring 64 secured to the bracket arm 44b to normally hold the detent 56within the recess 54 in the clutch element 52. The lever 60 at its topis formed with a tubular lug 61 within which one end 66a of a beltshifter 66 is secured by set screws 61a, and the other end of the beltshifter is formed with a hook 66b which engages the belt 36. Lever 60 isalso pivoted at 68 to a control lever 70, operation of which downwardlymoves the lever 60 about said pivot 68 and around the pivot pin 59 tothe right as viewed in FIG. 1, to withdraw the detent 56 from the slot54 in the clutch element 52 and simultaneously move the belt shifter 66to transfer the drive belt 50 from the pulley 48 onto the pulley 40 todrive said pulley 40 and with it the hub 38 and the disengaged clutchelement 52. The lever 60 has thereon two stop screws 61a, 61b whichlimit the movement of the control lever 70 as the inner end 71 thereofrides along the arm 44a of the bracket 44 in the course of depressingthe lever 70.

Mounted on the arm 44b of bracket 44 is a solenoid 72 having an armature74 to which is attached a lever 76 pivotally mounted at 78 in abifurcated bracket 80 mounted on the bracket arm 44b. The lever 76 isnormally biased by a coil spring 82, one end of which is anchored tosaid lever and the other end of which is anchored to a stud 84 extendingupwardly from the bracket arm 44b. The free end of the lever 76 isformed as a latching detent 86 having a shoulder 87 adapted to engageover the control lever 70 when said control lever is depressed to holdit in said depressed position. Supported by the bracket arm 44a near thetop thereof is a secondary bracket 88 which carries a normally openmicroswitch 90 which is adapted to be closed and so held by engagementtherewith by the lever 60 when the said lever is moved by operation ofthe control lever 70.

Trained over the pulley 34a is a drive belt 92 engaging over a pulley 94fixedly mounted on a drive shaft 96 at the input of a variable speedtransmission means 98 mounted on the table 46 to the rear of the machinehead 12. The variable speed transmission means may be of any preferredtype, such for example as disclosed in US. Patent No. 2,691,896 and hasa driven shaft 100 the speed of which may be varied in relation to thespeed of the drive shaft 96. Mounted on the shaft 100 inlongitudinallyspaced relation are a pair of circumferentially-adjustablecams 102 and 104. Rigidly mounted on the machine head above andpreferably rearwardly of the angular lever 28 for operating the cutterblade is a bracket 106 on which is pivotally mounted a lever 108 on apivot 109. The lever at one end carries a pin 110 overlying the arm 28aof the angular lever 28 and to the other end of said lever is connecteda rod 112, the free end 113 of which i angularly bent and overlies thecam 102. The lever 108 is biased by a coil spring 114 to maintain theend 113 in engagement with the surface of the cam so that when the highpoint 103 of the cam engages said rod end 113, the lever will be tiltedagainst the force of the spring 114 to cause the pin 110 to depress thearm 28b of the angular lever 28 to move the cutter blade out of cuttingposition.

The cam 104 carries an arm 105 (FIG. 6) which when said cam is rotatedengages an operating element 115 of a normally open microswitch 116 totemporarily close said switch until the arm clears said element 115.When the microswitch 116 is closed it completes an electrical circuitthrough the solenoid 72, since switch 90 has been previously closed, todraw the armature 74 to the left (FIG. 3) and with it the lever 76against the tension of spring 82 to disengage the detent 86 from holdingengagement with the depressed control lever 70, whereupon the leafspring 64 moves the lever 60 to simultaneously move the detent 56thereon to engage the slot 54 in the clutch element 52 to stop itsrotation, permit the microswitch 90 to open, and cause the belt shifterto move the belt 50 from the pulley 38 onto the pulley 48 and stop thesewing operation.

The duration of the sewing operation and hence the length of thestitching can be controlled by adjusting the speed of rotation of theoutput shaft 100. The timing of the relative operations of the cams 102and 104 can be controlled by adjusting said cams circumferentiallyaround the shaft 100.

With the attachments of the present invention mounted and operative on aconventional sewing machine of the types described, the primary sewingand slitting operations in a garment to provide piped pockets andbuttonholes therein can be performed in a single operation.

In FIG. 10 there is illustrated the relative initial positions of thevarious fabric work pieces in performing the sewing and slittingoperations. As illustrated in said FIG. 10 upon a strip of buckrambacking 117 are superposed the garment fabric 118, piping strips 120 inrelativelyspaced lateral relation and the pocket material 122. Tocommence the slitting 124 and the lines of stitches 126, the presserfoot of the machine is first depressed in a conventional manner intoengagement with the superposed fabrics, the cutter blade 26 is thendepressed into cutting position rearwardly of the needle, ashereinbefore explained, by raising the lever arm 28a and the controllever 70 is then depressed to initiate the sewing and slittingoperations. As hereinbefore described the depressing of the controllever 70 moves the belt shifter 66 from the pulley 48 to pulley 40 andsimultaneously disengages the detent 56 from the clutch element 52 todrive the shaft 16 by belt 36 and drive the variable speed transmissionby the belt 94 and its output shaft 100. Rotation of shaft rotates cams102 and 104 to control the relative lengths of the slit 124 and thestitching 126 respectively. When the microswitch 116 is closed by thecam 104 the attachment components are all returned to their initialpositions by the means hereinbefore described and the machine is nowready for a succeeding sewing and slitting operation.

It will thus be seen, that with the attachments of the present inventionapplied to a conventional sewing machine, an operator in preparing theslitting and sewing operations for pockets and the like in garments cando so after a proper setting of the output speed of the variable speedtransmission means and proper adjustments of the cams on the outputshaft of said variable speed transmission without depending upon visualinspection of the slitting and sewing operations and thereby greatlyspeedup the operation of performing that particular operation.

What I claim is:

-1. Attachment means for a sewing machine having a needle bar carrying aneedle, means for reciprocating said needle bar for performing a sewingoperation, a slit cutter movably attached to the needle bar forreciprocation therewith, means for moving said slit cutter from a normalnoncutting position to a cutting position for cutting operations whilesewing a plurality of sitches and vice versa and means for holding saidslit cutter in either of said positions, the attachment means comprisingmeans for operating the needle bar reciprocating means and means forautomatically withdrawing the slit cutter from its cutting position toits noncutting position at a predetermined time during the sewingoperation and for automatically stopping the sewing operation at apredetermined relation to that whereat the slit cutter is withdrawn.

2. Attachment means according to claim 1, wherein the means for stoppingthe sewing operation is operable at a predetermined distance beyond thatwhereas the slit cutter has been withdrawn.

3. Attachment means according to claim 1, comprising a variable speedtransmission means driven from a power source for the sewing machine,and cooperating means between the output end of the variable speedtransmission means and the slit cutter for operating the cutterwithdrawing means to move the slit cutter from its cutting position toits noncutting position.

4. Attachment means according to claim 1, camprising a variable speedtransmission means adapted to be driven from a power source for thesewing machine, and cooperating means between the output end of thevariable speed transmission means and the power source for operatingsaid means for stopping the sewing operation.

5. Attachment means according to claim 1, comprising a variable speedtransmission means driven by a power source for the sewing machine, andcooperating means between the output end of the variable speedtransmission means and the slit cutter for operating the cutterwithdrawing means to move the slit cutter from its cuting position toits noncutting position, and cooperating means between the output end ofthe variable speed transmission means and the power source for thesewing machine for operating said means for stopping the sewingoperation.

6. Attachment means according to claim 5, wherein the output end of thevariable speed transmission means is a shaft upon which is mounted twocircumferentiallyadjustable cams, one of said cams operating said cutterwithdrawing means for moving the slit cutter from its cutting positionto its noncutting position and the other of said cams operating saidmeans for stopping the sewing operation.

7. Attachment means according to claim 4 wherein the cooperating meansbetween the output end of the variable speed transmission means and thepower source for the sewing machine, comprises a stub shaft upon whichis loosely mounted a first pulley driven by a belt from the powersource, a second pulley having a hub and a single rotatable clutchelement, said second pulley, hub and clutch element being rotatable as aunit, a spring-biased lever having a detent for normally holding theclutch element against rotation, a third pulley fixed on the shaft of aneedle-bar reciprocating means, first drive means between said hub andsaid third pulley, second drive means between said third pulley and theinput of the variable speed transmission means, belt shifting meansoperable by the spring-biased lever for moving the belt from the firstpulley to the second pulley and vice versa and operable when moving thebelt from the first pulley to the second pulley to release the clutchelement, and said cooperating means between the output end of thevariable speed transmission means and the power source further causingthe detent device to move into engagement with the clutch element andmove the belt from the second pulley onto the first pulley to stop thereciprocation of the needle bar.

8. Attachment means according to claim 7, wherein the cooperating meansbetween the output end of the variable speed transmission means and thepower source comprises a control lever pivotally connected to thespring-biased lever, a second pivoted lever formed with a detent, springmeans biasing the second lever so that the detent thereon will engageover the control lever to hold it in its operative position when movedinto said position and electrisally-controlled means for restoring thevarious recited means to their normal positions and stopping theoperation of the sewing machine.

9. Attachment means according to claim 8 wherein theelectrically-controlled means comprises a solenoid including anarmature, two normally open microswitches, one of said switchescontrolling said solenoid; the second lever being pivotally connected tosaid armature, and the other of said switches being operable by theoutput end of the variable speed transmission, whereby when the controllever is depressed the machine will start the sewing operation and whenthe second switch is closed the circuit through the solenoid will closeand operate it to withdraw the second pivoted lever from latchingengagement with the control lever and the various spring means willfunction to return the respective parts to their normal positions of themachine at rest.

10. Attachment means according to claim 1, including a clamp mounted onsaid needle bar, a cutter blade holder pivotally mounted on said clamp,a slit cutter blade fixedly carried by said holder, said means forholding said cutter in either of said positions comprising spring meansnormally biasing the cutter blade holder for positioning the blade innoncutting position and camming means pivotally mounted on said needleclamp for moving and holding the cutter holder, in opposition to thebiasing action of the spring means, into cutting position.

11. Attachment means as defined in claim 10- wherein the cutter blade isrearwardly and laterally disposed in relation to the needle in thedirection of the sewing and slitting operation and is movable out ofcutting position during the sewing operation.

12. Attachment means according to claim 11 wherein the said attachmentmeans is applied to a two-needle sewing machine and the cutter blade isdisposed between the needles.

References Cited UNITED STATES PATENTS 678,993 7/1901 Bissinger 112--1251,936,381 11/1933 Corrall et al. 1l2-68 2,581,046 1/1952 Rich 112--682,620,759 12/1952 Pantusco et al. 11268 3,361,098 1/1968 Seaman 112128XR H. HAMPTON HUNTER, Primary Examiner.

US. Cl. X.R. 112-125, 128

